RT info:eu-repo/semantics/article
T1 Cytosolic organelles shape calcium signals and exo–endocytotic responses of chromaffin cells
A1 García García, Antonio
A1 Padín, Fernando
A1 Fernández Morales, Jose Carlos
A1 Maroto, Marcos
A1 García-Sancho Martín, Francisco Javier
K1 Calcio
K1 Bioquímica
AB The concept of stimulus–secretion coupling was born from experiments performed in chromaffin cells 50years ago. Stimulation of these cells with acetylcholine enhances calcium (Ca2+) entry and this generates atransient elevation of the cytosolic Ca2+ concentration ([Ca2+]c) that triggers the exocytotic release of catecholamines.The control of the [Ca2+]c signal is complex and depends on various classes of plasmalemmalcalcium channels, cytosolic calcium buffers, the uptake and release of Ca2+ from cytoplasmic organelles,such as the endoplasmic reticulum, mitochondria, chromaffin vesicles and the nucleus, and Ca2+ extrusionmechanisms, such as the plasma membrane Ca2+-stimulated ATPase, and the Na+/Ca2+ exchanger.Computation of the rates of Ca2+ fluxes between the different cell compartments support the proposalthat the chromaffin cell has developed functional calcium tetrads formed by calcium channels, cytosoliccalcium buffers, the endoplasmic reticulum, and mitochondria nearby the exocytotic plasmalemmal sites.These tetrads shape the Ca2+ transients occurring during cell activation to regulate early and late steps ofexocytosis, and the ensuing endocytotic responses. The different patterns of catecholamine secretion inresponse to stress may thus depend on such local [Ca2+]c transients occurring at different cell compartments,and generated by redistribution and release of Ca2+ by cytoplasmic organelles. In this manner,the calcium tetrads serve to couple the variable energy demands due to exo–endocytotic activities withenergy production and protein synthesis.
PB Elsevier
SN 0143-4160
YR 2012
FD 2012
LK http://uvadoc.uva.es/handle/10324/6339
UL http://uvadoc.uva.es/handle/10324/6339
LA eng
NO Cell Calcium, 2012, vol. 51, p. 309-320
NO Producción Científica
DS UVaDOC
RD 27-nov-2024